Liquid-level gage.



T. WALKER.

LIQUID LEVEL GAGE. AAPPLYlcMloN min 1An.|o.|9|1.

Patented Dec. 11,1917.

BY *fr L TTQRNEYS WITNESSES if/@74u UNITED STATES- PATENT ermee.

THOMAS WAL-RER, F LOISVILLE, KENTUCKY.

LIQUID-LEVEL GAGE.

6 State of Kentucky, have invented a; certain new and useful Improvement in Liquid- Level G ages, of which the following is a. specification. l

My invention relates to liquid gages, and

10 it consists in the combinations, constructions, and arrangements herein described and claimed.

An object of my invention 1s primarily to rovide =a gasolene gage of the type in which the hydrostatic head of the liquid in the fuel tank determines the position of `a liquid in a gage glass, the twobeing connectedby means of an air tube, the novel feature of the invention being the provision of means by -which the error in the reading of i scribed, in which `the error is reduced to a vls the gage glass, due to differences in temperature, 1s rendered negligible.

A further object of my invention is to provide a gasolene Agage of the type deminimtun, and in which the parts are simple in constructionand are, therefore, not liable to easily et out of order.`

A' furter object of my invention is to provide a gasolene gage in which the movement of the vehicle has no appreciable effect on the accuracy ofthe ga e glass, due to, the particular manner in w ich certain partsare arranged.

r ,Otherl objects and advantages will appear in' the following specification, andthe novel features of the invention will be particularly pointed out in the-appended claims.-

My invention is illustratedin the accom` panying drawings forming part of this application, in wh1ch:

Figure lshows the general arrangement of the parts, the gasolene tank being shown in section;

Fig.' 2 1s an enlarged sectional detail view of the gage glass holder;

Fig". 3 is a plan viewlofan auxiliary air box, a portion of the box lbeing shown in section;

` Speclcation of Letters Patent.

Patented Dec. 11, 1917.

Application filed January 10, 1917. Serial No. 141,626.

Fig. 4' is a face view of a portion of the ga e glass, and

' fig. 5 is a section throu h the box".

In gasolene gages which ependfor their operation upon the movement of-a column of liquid due to, changes in the hydrostatic head in the fuel tank, or, inother words, to the amount of fuel in the tank,'and which make use of air as a means of transmitting the pressure, large variations of tempera ture are apt to Vcause the air to expand or contract and Atolrenderl the reading therefor inaccurate, and often wholly useless.

The present invention is designed to re duce to a minimum, that is to say, to a nerrligible quantity, the error which must axl- Ways exist in gages of this'type due to the differences in temperature.

In carrying outmy invention I make use of a tank of any suitable type, such as that shown at A in Fig. 1. The drawing shows `a tank of a substantially square cross section, but 'obviously it may be .of other forms, Without departing from the spirit of the invention. An air pipe B is connected at one end with a U shaped tube Gwliich Contains a liquid, such as mercury, and which is provided with a scale D. At one end of the tube C is a valve V, while a second valve V is carried by the tube B. A iioat is provided in the U-shaped tube C for indicating thleJ height of the column of liquid in the tu e.

The U-shaped tube C is preferably located 4in a holder E provided with a lens F, by

means ofV which thescale`D-ma be easily read.4 'The tube is preferably tilted at an4 angle, so as to be easily-seen by the driver of the vehicle. The holder E is preferably ,secured to the dash G of the automobile or other vehicle.

The pipe B, as will be seen from Fig. 1, passes into the gasolene tank A. At thev ottom of the gasolene tank is a box H which has in it a coiled tube K havin one.. end opening into the gasolene tan as shown at `lz., and the opposite end opening into thebox H.4 The pipe B communicates with the interior o f. the box^H at its top.

` placed always o'n 15' adjacent column.

20 however, thereI of temperature.

From the foregoing descriptioiof the val rions parts of the device, theorperation thereof mayv be readily understo The gasolene tank may beV located at any convenient part ofv the vehicle, but the provision of the pipe B permits the gage'to be the dash. Consider the action of the device if the box H were not present, i. e., if the tube B terminated near the bottom of the tank. If gasolene is poured into l'the tank, the air pressure in the tube B will cause the depression of the column of mercury in the arm bearing the scale D, and the'rise of the mercury in the If the temperature could be maintainedv constant, then the amount of gasolene in the tank could be accurately observed by the difference in hei lit of the columns of mercury. In vactua practice is a considerable variationv 'Let us lassume that the temperature'of all the partsis lowered 100 F. It is quite ap arent that the air contained in the tube B etween the mercury and the gasolene would halfv inches square the mercury.

contract about one-fifth yorto about fourifths 'of its former volume, and gasolene will be vdrawn up inside of the tube B to a distance a proximately one-fifth of the lengthvoft etube.. As the asolene is drawn upfinto the tube, llfthe head `e'tween the top of the asolene in the tank and the top of the gaso .tube is reduced, andthe-difference in eleva tion-'of the columns of mercury is correspondingly reduced. Obviously, unless the variation due to temperature can be offset, the device would have little or no practical va1ue. y Now, by adding an auxiliary air space, such as that in the box H, the error is reduced to a minimum. For, let us assume that the tube from the tank to the dashboard 'is ten feet long by one-eighth of an inch diameter inside, and that a box twoand oneby ive-eigliths inches dee communicates, by means of the tube, wi the U-shaped gage glass, containing The cubic contents ofl the tube would be 1.47 cubic inches, and the contents of the box 3.92 cubic inches; Therefore, the total volume of air contained in the .tube and the box would be 5.39 cubic inches. A

y Assuming a maximum reduction of 150 F., this would cause the air to contract aboutd 1.24 cubic inches; which would one-fourth .or cause a rise of the gasolene'in the box H' about two tenths of an'inch. This could'be disregarded for practical purposes, as far las its eect on the movement ofthe column of .mercury is concerned. t

1n order to prevent the'movement of the coil This 'the end of the tube,

vthe U-shaped tube.7

ene in the' "ramon the air in the box H to ene tank, I provide the. rovides a passage for asolene which is disposed horizontally, that is to say, at right angles to the line in which t-he shocks or jars will come, and allows the vehicle from causin escape into the gaso liquidto flow through the tube without af- ,fecting the h drostatic head.

The valve f is similar to a. bicycle valve, and is for the purpose of charging the tube B with air from time to time, if necessary.

v Thevalve V is for the purpose of reventing the mercury from being force out of since this' valve will .65' the close as soon as the mercuryreaches ithwhen A the air is being forced into the tube `Instead of having a scale on a oat within the scale may be on the outside, but in using the floating scale one can-see ata lance the diflerencesin'height -of the two co umns of mercury, while with a' scale on the outside of the tune, one has to calculate this difference.

' The device described above will reduce the error due to vaporization as well as to- Vaporization will increase temperature. the error, but the 'device will oiset it satisfactorily. Vaporization is, of course, de pendent upon the temperature (and pressure),

mean a change in vapor pressure. l

Obviously other liquids besides mercuryeo Y and -av change in temperature would might be used in the gage lass, without def part-ing from the spirit an vention.

I caimz; 1 l 1. n a aso ene ga e, a e lass havin a liquid terein and ein govgided with scale to indicate the heig it of the liquid, a casing or box disposed vin the 'gasolene ytank scope of the-inon the bottom thereof,.said casing' having a horizontal coil disposed tank on the bottom thereof, means for establishing communication between said ga and said casing, a horizontal coiled tube disposed within the casing, one end y of said" tube communicatin with the linterior of the gasolenetank and' t e otherv end of the tubecommunicating with the interior of the cas- 12o,

ing, said tube being of less diameter' than the height of the casing.

therein, said coil communicating at onegend withl the interior' iis 3. The combination with a giasolenev tank of a gage glass, a' box or casin disposed within the gasolene tank on t e bottom i `thereof, a pipe connecting the top of the casing withsaid gagel glass, -a tube 1 posed in horizontal pnstion, one` end of ig-lil relatively gncompnrdsaid tube being mesure@ to the side of the witfl the tank, a conduit digposed within the casing 1nd commu nf with. the interior casing, said conduit beiugm horizontal po- Of the, casing, tima/ppi 'ie end being open to sition, one end of the conduit communicatthe interim n Liesing, me and of the ing with the inrior of the gnsoler s tank tube being mibstmi ily :il: right angles t0 and the other end'oftlm conduit bng 0pm: the other and. to the interior of-ithe. casing, 'and means ifm.' 4. ,The pombinaiian 'with a gasulnp, taink establishing communication betwaem the cas of a gicge g,'lls1 11 him m* casing disposed ingand the' gage. 4 1o Within the gsmlmm tank, said box haw l THMS WALKER. 

